Refrigeration apparatus



une 14, 1938. F. Mj RAVE@ REFRIGERATION APPARATUS Filed May 1, 19:57

2 Sheets-Sheetl lllllllllllll Il Illlllllllllllllll 7 I I l l I l I l Il l I I I ll- June 14, 1938.

F. M. RAVER 2,120,76?

REFRIGERATION APPARATUS Filed May l, 1937 2 Sheets-Sheri*I 2 Bmsentor f@Bg QQ/, jt

(Ittomeg lll) Francis M. Raven, 'Yorin lla., assigner to Yori; iceMacery @oi-poration, Yorin lPa., a corpo ration ci Delaware applicationMay i, roer, serial sa. maaar t @laimsi This invention relates tocondensers and particularly to condenser cooling towers used chiefn -lyfor lidueylng reirigerants, in mechanical reirigerating systems.

The invention, though applicable to any condenser using a cooling tower,will be described as embodied in a c ondenser cooling tower; i. e..

a device in which the heat transfer surface of the condenser is in thetower and thus directly afiected by the air current and the water spraysin the tower.

in any cooling tower part of the sprayed water is evaporated, and thelatent heat of vaporization of the evaporated water accounts for a largeproportion of the heat rejected. Theoretically, the temperature at whichcondensation occurs approaches the wet bulb temperature of thecirculated air, butactually it is substantially higher than this unlessmuch power be consumed in atomized spraying.

Conventional condenser cooling towers have cooling coils for thecondensed liquid located below the condensing leaving such coils.

coils and in the path of water In such devices the iinal temperature ofthe condensed liquid is not lower than the temperature of coils.

water leaving the condensing Substantial economies can be eiected byreducing the temperature of the liquid refrigerant.

For example, with heat such as Freenarefrigerant of low latent 12(trade-name) the increase in compressor capacity is approximately 1/2 of1% for each Fahrenheit degree reduction of liquid temperature,

because iiash gas is reduced correspondingly enhanced.

The present invention provides method and means for reducingsubstantially to the the temperature of the liquid wet bulbtemperatureof the cooling tower air, without requiring complicated additionalapparatus and without material increase in power consumption for aircirculation or spraying.

The invention is based on the facts that make@- up water is required byany cooling tower, and

that city water temperatures, under normal conditions, approximate thewet bulb air temperature. In carrying out `the invention, city water isused for make-up. and the make-up water, or

a substantial part thereof,

the air entering the cooling coil. The temperature etv the is finelyatomized in cooling tower for the purpose and air to the wet bulbtembefore they encounter the at the wet bulb air-co0l the condensedliquid.

in this way the lowest temperae attainable by air circulation, ycombinedwith water, spray, is secured in a simple and axaercially practicablemanner.

Obviously, the presence of a cooling tower using 5 maire-up water, isthe controlling factor. The specific form of the condenser is.secondary. As stated above, the invention is capable of convenient usewith a condenser cooling tower.

Such an installation will now be described as lo the preferredembodiment, but is intended as exe emplary and not limiting.

lin the drawings,-

Fig. i is a iront elevation of a condenser cooling tower and liquidsub-cooler, embodying the lo invention. The screen at the air entranceis omitted. Certain internal parts are indicated in dotted lines, andothers are rendered visible by breaking away parts of the casing.

Fig. 2 is an elevation ci the lett end of the de- 20 vice shown in Fig.1.

Fig. 3 is a section on the line tof Fig. l.

Fig. 411s an elevation oi the right end of the device shown in Fig. l.

The base of the device comprises a water pan 25 or sump 6, in' whichrests a. rectangular housing l enclosing the condenser cooling towercomponents. Housing' l has a forward extension 8 which houses thesub-cooler for condensed liquid.

Air enters at 9 through a port in the front of 30 extension 3, theopening being protected by a removable screen ll (see Figs. 2i=, thescreenbeing omitted from Fig l). From the interior of extension, 8 theair passes to the interior of main housing l via opening l2 (see Fig. 3)and 35 flows thence upward to a seriesof centrifugal fans I3 (threebeing shown) which discharge through hoods lil intended to be connectedby ducts (not shown) to any suitable point of air discharge. Theopenings 9 and l2 extend the 40 entire length of the front of therespective housings, so that the air stream is coextensive with theentire length or both housings.

The runners of the fans I3 are mounted on a common shaft il, whichextends beyond the end 45 of housing 1, and is driven by motor l5throughv a multiple V-belt drive indicated at I6. The fans extendinghorizontally substantially the entire length of housing 1. The showerpipes have each a series of spaced, downwardly directed spray heads 26,as indicated. Pump I9 runs continuously when the condenser is inoperation.

The condenser comprises an upper (gas) header 21, and a lower (liquid)header 28 connected by a plurality of sinuous tubes 29, nine beingindicated, the tubes 29 being spaced across the air path and having aplurality of horizontal passes arranged to be wetted by spray from heads26. The high pressure gas line `from the compressor (not shown) isindicated at 3I and leads to the gas header 21. The liquid header 28 isconnected by pipes 32, 33, with the receiver 34, which is below tubes29, and below a coill support 30 which supports the condenser coil 29. Apressure relief valve is indicated at 35.

From the lower portion of receiver 34 a pipe 36 leads to entrance header31 of the liquid cooler. Between thisand an exit header 38 are aplurality of sinuous tubes 39 (two being shown). Each tube makes severalhorizontal passes,l and a series of closely-spaced plate ns 4I aremounted on the tubes 39 to increase the heat transfer surface. Theliquid cooler, comprising the headers, tubes and ns, overlies and iscoextensive with the opening I2, the fins being parallel with and thetubes transverse to the path of air flow across extension 8 fromentrance 9 to port I2.

From exit header 38 the liquid line 42 leads to expansion valve 43.Valve 43 typiiies means for feeding liquid refrigerant to an evaporator(not shown) which, as usual, is connected to the 'suction of thecompressor (not shown) or its equivalent.

It is important to observe that, as above stated, the pipe 36 leads fromthe lower portion of the receiver 34 so that the receiver, because it ispartially filled with liquid refrigerant, serves as an isolating trapbetween the condenser proper and the sub-cooler. In order that thesub-cooler may perform its intended function, entrance of uncondensedvapor from the condenser proper into the sub-cooler must be prevented.Otherwise the sub-cooler would become merely an extension of thecondenser and would operate to condense and not to sub-cool.

Arranged in front of tubes 39 is a spray pipe 44 with atomizing nozzles45 arranged to spray finely atomized water into the air entering at 9against the tubes 39 and ns 4I. Part of this water is evaporated andtheremainder falls to sump 6 and serves as a part of the make-up for waterevaporated as an incident to condensing the refrigerant in tubes 29. q

The water supplied to pipe 44 is city water under service pressurearriving via pipe 46. 'I'he pipe 46 also supplies valve I1, which undercontrol of float I8, maintains the water level in pan 6 substantiallyconstant.` From pipe 46 a branch 41 leads to the regulating valve 48.'Ihis is a pressure actuated stop valve subject to receiver pressuretransmitted through tube 49. Valve 43 is arranged to open the waterpassage in response to normal receiver pressure, and close it when thereceiver pressure falls below normal, as it does when the compressor isshut down. From valve 49 the water passes through pressure reducingvalve 5I to spray pipe 44. A gage 52 indicates the pressure in the spraypipe.

The arrangement is such that at the maximum rate of supply vthroughspray pipe 44, there will not be more than enough water for make-uppurposes. The oat valve supplies any deficiency.

entering the cooling tower; and means for spraypan 6 and thence upwardsover the coils 29, while another portion of the air flows through theliquid cooler to the opening I2 and thence upwards over the coils 29.The resistances to ow in the two paths are so chosen that an adequateflow of air over the liquid cooling coils is had.

It is not necessary to pass all the air used in the condenser over theliquid cooling coils, and. it will be observed further that not all thewater sprayed by the nozzles 45 is evaporated.

The principle of operation will be readily understood. The condensedliquid is cooled by the coldest available air and water after they havebeen cooled by evaporation of the water, to a temperature which issubstantially the wet bulb temperature of the air. This water not onlyacts directly on the cooling surface but supplies part of the make-up.

Thus there is no appreciable increase in water consumption, and no poweris used in spraying the liquid cooling water, since city supply pressureis used for this purpose.

As already suggested, the4 invention is applicable to various types ofcondensers including -cooling towers and the specific embodiment abovelimiting.

What is claimed is:

1. 'I'he combination of a surface condenser; a cooling tower includingmeans for circulating air through the tower, means for bringing watercontained in the tower into intimate contact with said circulated air tocool a part of the water by evaporation of another part, and means forprogressively supplying makeup water to replace the part evaporated;means for causing said cooled partof the water to cool the condenser; asurface cooler connected to receive liquid condensate from thecondenser, the connection being such as to inhibit the` entrance ofuncondensed vapor into the surface cooler; and means for causing atleast a part of the circulated air and makeup water as they approachsaid tower conjointly to cool said surface cooler.

2. 'I'he combination o`f a cooling tower and associated condenser, thecondenser being cooled at least in part by water which is cooled in thecooling tower by evaporation of a. part thereof in an air streamcirculated through the tower; a surface cooler connected to receive andcool liquid condensed in said condenser, the connection being such as toinhibit the entrance of uncondensed vapor into the surfacecooler,andsaid surface cooler being in the path of the air stream ing makeupwater into heat exchanging relation with said surface cooler and forcausing unevapov rated portions thereof to enter said cooling tower.

3. 'I'he combination of a cooling tower and associated condenser, thecondenser being cooled 70 beingV such as to inhibit the entrance ofuncondensed vapor into the surface cooler, and said surface cooler beingin the path of the air stream entering the cooling tower; and means forsupplying makeup water to said cooling tower, at least a portion of saidmakeup water being sprayed into said entering air stream to cool the.same in advance of its vcontact with said surface cooler.

4. The combination oi a casing including a water collecting sump; asurface condenser in said casing; means for passing air through saidcasing in contact with said condenser; means for spraying water fromsaid sump into contact with said air and condenser and for returningunevaporated spray water to said sump; a surface cooler in the path ofair entering said casing and connected to receive and cool liquidcondensed in said condenser the connection being such as to inhibit theentrance of uncondensed vapor into the surface cooler; and means forsupplying makeup water to said sump, said means being arranged to sprayat least a portion of the makeup water into heat exchanging relationwith the entering air and said surface cooler.

5. A vapor condensing and liquid cooling device comprising two surfacecoolers connected in series, the connection being. such as to inhibitthe passage-of uncondensed vapor from the first to the second cooler thefirst cooler serving to water into heat exchanging relation condense andthe second serving to sub-cool volatile medium passed therethrough inthe order stated; means for passing a stream of air nrst into heatexchanging contact with the second cooler andthen into heat exchangingcontact with the nrst cooler; a water collecting sump; means forspraying water from saidA sump into contact with the nrst cooler and forcausing return of unevaporated portions thereof to said sump; and meanstor supplying cold makeup water to said sump, said means including meansfor spraying at least a portion of said makeup with said second cooler,prior to delivery to said sump.

6. The combination of a surface condenser; a liquid cooler oi thesurface type to which the condenser delivers; means for maintaining aliquid seal between said condenser and cooler whereby the entrance ofnncondensed vapor from the condenser to the cooler is prevented; meansfor circulating air lin a stream in heat exchanging relation with thecooler and then with at least a substantial portion oi the condenser;means for supplying cooling water and for spraying it into the air asthe latter exchanges heat with the .cooler; and means for spraying thennevaporated remainder or said water into the portion of the air streamwhich exchanges heat with the condenser.

FRANCIS M. RAVER.

DISCLAIMER 2,120,767 .-Francts M. Raver, York, Pa. REFRIGERATIONAPPARATUS. Patent dated June 14, 1938. Disclaimer filed June 29, 1939,by the assignee, York Ice Machinery Corporation. Hereby enters thisdisclaimer to claim 2 in said specification.

[Ocz'al Gazette July 25, 1.939.]

